This invention belongs to a technical field of multiple automatic packing machines capable of automatically seal-molding a plurality of stick-like packing products at a time, and particularly, it relates to a packing film feeder suited to be used for such a multiple automatic packing machine.
As disclosed for example in U.S. Pat. Nos. 5,634,324, 5,408,807, etc., the conventional multiple automatic packing machine is constructed such that operations of slitting, vertical sealing, lateral sealing, filling of material to be packed and cutting are carried out with respect to rolls of packing material formed from a uniformly printed wide sheet film in accordance with the number of row.
The construction of the above conventional multiple automatic packing machine will be described in detail with reference to FIG. 3. Reference character F denotes a take-up roll with a printed wide packing material taken up thereon, AS, AT denote packing material supply rollers rotatable by a motor (not shown), BX . . . denote slitters for slitting the packing material FX into a plurality of packing films Fa . . . , and Ca, Cb denote guide rollers.
Similarly, reference character D . . . denote feed pipes for filling material to be packed laterally equally spacedly disposed in side by side relationship, E . . . denote forming members for forming incoming packing films Fa . . . around the feed pipes D . . . , X denotes a vertical heat sealer for vertically sealing opposite end edges of the respective packing films Fa . . . into a sleeve-shape as a whole, and Y denotes a lateral heat sealer for applying a lateral seal to the vertically sealed sleeve-like packing films Fa . . . When this lateral heat sealer Y performs a lateral sealing, the material to be packed is filled into each of the packing films Fa . . . which has been seal molded into a bag-like configuration through each of the feed pipes D . . . Then, the lateral heat sealer Y performing a lateral sealing to each of the packing films Fa . . . is moved downwardly by one pack portion to withdraw each of the packing films Fa . . . by one pack portion.
Thereafter, the lateral heat sealer Y is laterally opened to release a lateral sealing and in that state, it is raised back to a position ready to perform a lateral sealing. In that position, the lateral heat sealer Y performs a lateral sealing once again to tightly seal a mouth of each sealed bag filled with the material to be packed and a cutter (not shown) vertically cuts a center line portion of the lateral sealing. By this, one cycle of multiple sealing operations is completed.
In FIG. 3, reference character TN denotes a hopper containing a material to be packed, Da . . . denote upper end inlet ports of the feed pipes D . . . inserted into a bottom portion Ta of this hopper TN, Ma . . . denote rotary shafts whose lower end portions are inserted into the feed pipes D from the inlet ports Da . . . , Ms . . . denote material filling screws formed on lower end portions of the rotary shafts Ma . . . inserted into the feed pipes D . . . , and HP generally denotes an automatic packing portion including the heat sealers X, Y.
Similarly, reference character M . . . denote motors for rotating the rotary shafts Ma . . . disposed on an upper surface portion of the hopper TN. When the screw Ms is rotated within the feed pipe D, the material to be packed contained in the hopper TN is taken into the feed pipe D through the inlet port Da. Then, the material to be packed is smoothly an forcibly filled into the packing film Fa which has been seal molded into a bag-like configuration through the feed pipe D having a small diameter. Even a material to be packed, which is in the form of powder or in a viscous state, can be supplied under compression in an extremely stable manner by rotation of the screw Ms.
In FIGS. 2 and 3, reference characters P . . . denote packed products each of which has been seal molded into a stick-like configuration by the multiple automatic packing machine, Pa . . . denote vertical seal portion, and Pc, Pb denote upper and lower lateral seal portions cutting into two by a cutter.
As mentioned above, according to the conventional multiple automatic packing machine of FIG. 3, a number of stick-like packing products P . . . can be packed automatically at a time. However, there is a need of providing rotational drive motors M . . . on the upper end portions of the respective rotary shafts Ma . . . in order to rotate the screw Ms for filling a material to be packed into each feed pipe D and in addition, there is a need of enlarging a distance between each adjacent rotary shafts Ma . . . , i.e., a distance between each adjacent feed pipes D . . . so that the motor M . . . will not interfere with each other. The enlargement of the distance gives rise to the problems to be described hereinafter.
Since the packing films Fa . . . , which have been slit by the slitters Bx . . . , are advanced straight ahead, they cannot be directly delivered to and form around the feed pipes D . . . which are arranged side by side relationship at an enlarged distance therebetween as mentioned above. Eventually, it becomes necessary to forcibly enlarge the distance between each adjacent feed pipes D . . . of the filling device in a lateral direction in such a manner to coincide with the distance Fb between each adjacent packing films Fa . . . as shown in FIG. 3. As a consequence, the packing film Fa is degraded in quality by traces of wrinkles and folds, thus resulting in poor final products.